Agent for stabilizing foodstuffs and cosmetic agents, and a method for the production thereof

ABSTRACT

The invention relates to a method for producing an antioxidatively active extract which can be used in particular for stabilizing foodstuffs and cosmetic agents. According to the method, non-enzymatically browned grain germs, or a mixture containing non-enzymatically browned grain germs, is/are extracted using a solvent or solvent mixture (e.g. ethanol or an ethanolic mixture) having an E T   N  value ranging from 0.6 to 0.8, and the extracting agent is then optionally separated off. The invention also relates to a method for stabilizing unbrowned grain germs in which these unbrowned grain germs are mixed with non-enzymatically browned grain germs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns an agent for stabilizing foodstuffs and cosmeticagents as well as a process for production thereof.

Lipid-rich foodstuffs and cosmetic agents can become rancid inparticular as a result of a lipid-peroxidation processes(autooxidation). The rancidification of foodstuffs (frequentlyrecognized by their prickly, unpleasant taste) and cosmetic agentsresults in their becoming unusable.

2. Description of the Related Art

It is already known to add natural or synthetic antioxidants tofoodstuffs and cosmetic agents in order to inhibit their autooxidation.Typical anitoxidants are, for example, tert-butylmethoxyphenol(tert-butylhydroxyanisol, BHA) and di-tert-butylmethylphenol(Butylhydroxy-toluol, BHT), ester of gallic acid, tocopherol (vitamin E)as well as ascorbic acid and their fat soluble esters. There is howevera great demand for further antioxidants, and in particular for thosewhich can be added to foodstuffs, without having the legal character ofa listed food additive which requires regulatory approval.

SUMMARY OF THE INVENTION

It was the task of the present invention to provide an antioxidant whichis in particularly suitable for stabilizing lipid-rich foodstuffs.

This task is inventively solved by the provision of an antioxidationeffective extract, wherein the extract can be produced by extractingnon-enzymatically browned grain germs, or a mixture containingnon-enzymatically browned grain germs, using a solvent or solventmixture having an E_(T) ^(N)-value ranging from 0.6 to 0.8 andoptionally separating off the extraction agent.

For E_(T) ^(N)-value and its determination, see Christian Riechhardt,Chem. Rev. 1994, 2319-2358.

The grain germs are preferably separated from the chaff of the grains inconventional manner prior to roasting, in particular separated from thecortex, the epidermis (seed cover, bran), the endosperm (starch andgluten) and the aleurone layer, since these residual components take upa large volume in comparison to the germ and thereby raise the cost ofthe roasting process.

In accordance with a suitable process according to the invention forproduction of an antioxidative effective extract, non-enzymatic brownedgrain germs or a mixture, which includes non-enzymatic browned graingerms, are extracted with a solvent or solvent mixture having a E_(T)^(N)-value between 0.6 and 0.8 and optionally separating the extractingagent.

The extracts obtained with such a polar extraction agent, for examplewith ethanol or an ethanol solution, are surprisingly suitable forstabilization of lipid-rich foodstuffs as compared to extracts whichwere obtained with extraction agents of lower polarity (such as forexample acetone or diethyl ether). This could not be predicted a priorisince it is known that polar extraction solvent agents first extractpolar contents from the respective material being extracted, and polarsubstances were generally considered to be unsuitable for thestabilization of lipid-rich foodstuffs on the basis of their low fatsolubility.

The grain germ (Poacae,=Graminaceae) extracted in accordance with theinvention are preferably wheat, barley or other germ from grains fromthe subfamily of Pooideae; also corn germ and other germ of thecorresponding other grain subfamilies can be employed with good success.

The non-enzymatic browning typically occurs by roasting, and thispreferably under the action of dry heat at a temperature of preferablybetween 50 and 200° C.; roasting temperatures in the range between 120and 170° C. are preferred and particularly preferred are roastingtemperatures of between 140 and 160° C. An increase in the roastingtemperature generally brings about, in the mentioned temperature ranges,an improvement in the antioxidative effect of the corresponding extract(see Example 10 below). With an increase in the roasting temperatureabove 160° C., however, no significant improvement in the antioxidativeeffect is achieved any longer. At roasting temperatures belowapproximately 160-170° C. only insignificant amounts—if any—of toxicby-products or minor constituents are formed, while at highertemperatures considerable amounts of these substances could result.

Roasting is preferably carried out for 5-100 minutes.

During browning, products of the Maillard reaction are formed, and ithas now been accomplished, by extraction with the mentioned solvents orsolvent mixtures, to obtain a corresponding extract which possess asurprisingly high antioxidative effectiveness. Control tests havesurprisingly shown that fractionations of this (total) extract do notresult in substance compositions which possess an improved antioxidationeffectiveness in comparison to the untreated (total) extract, but ratherthat the obtained (total) extract itself possess the highesteffectiveness. This can be traced back to a surprisingly synergisticeffect of the extract component substances.

Even though a fractionation does not lead to an improvement in theantioxidative properties of the inventive extract, it is howeversometimes useful to separate out the aroma and/or color forming minorconstituents of the extract. For this, the person of ordinary skill inthe art can use the conventional separation processes.

In accordance with a further aspect, the invention includes in generalthe use of extracts of non-enzymatically browned grain germ asantioxidative effective agents for stabilization of foodstuffs, inparticular lipid-rich foodstuffs or cosmetic agents, wherein forproduction of the extracts any solvents or solvent mixtures, inparticular those which are liquid at room temperature (20-25° C.), canbe employed as extraction agents.

However, particularly suitable for use as antioxidants are the extractsin accordance with the invention, in which an extraction agent,particularly from the ethanol including group of the dipolar proticsolvent agents, is employed in their production, and in particular onewith an E_(T) ^(N)-value between approximately 0.6 (1-propanol) andapproximately 0.8 (glycol). These (polar) extracts are surprisingly notinferior to the conventional synthetic antioxidants, and in certainrespects are even superior to them.

The invention concerns also foodstuffs and cosmetic agents, whichinclude a stabilizing effective amount of the inventive extract or afraction of such an extract.

The extracts according to the invention are particularly suitable forstabilizing lipid-rich foodstuffs such as pure conventional plant oils(for example corn oil) or complex, sensitive foodstuffs (such as, forexample, unbrowned wheat germ itself). For example, unbrowned wheat germcan be stabilized by roasting a small portion of the wheat germ,extracting the roasted wheat germ with ethanol, and applying the extractto the unbrowned wheat germ.

It has surprisingly however been found within the framework of theinvention, that for stabilization of unbrowned grain germ it is not onlythe inventive extract, but rather also non-enzymatic browned grain germitself, that can be employed, wherein the unbrowned grain germ is mixedwith the non-enzymatically browned grain germ. Herein preferably theratio of the non-enzymatic browned to the unbrowned grain germ isadjusted to a mass mixing ratio in a range of from 2:100 to 8:100,preferably however from 2:100 to 4:100.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 Peroxide values of conventional wheat germ oil, which was storedat 50° C. with various antioxidants.

FIG. 2 Concentration of conjugated diene-hydroperoxides in conventionalwheat germ oil, which was stored at 50° C. with various antioxidants.

FIG. 3 Concentration of α-tocopherol in conventional wheat germ oil,which was stored at 50° C. with various antioxidants.

FIG. 4 Peroxide values of conventional wheat germ oil, which was storedat 60° C. with various antioxidants.

FIG. 5 Concentration of conjugated diene-hydroperoxides in conventionalwheat germ oil, which was stored at 60° C. with various antioxidants.

FIG. 6 Concentration of α-tocopherol in conventional wheat germ oil,which was stored at 60° C. with various antioxidants.

FIG. 7 Peroxide value in tocopherol-free corn oil, which was stored at60° C. with various antioxidants.

FIG. 8 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 60° C. with variousantioxidants.

FIG. 9 Peroxide values of treated wheat germ, which was stored at 50° C.with various antioxidants.

FIG. 10 Concentration of conjugated diene-hydroperoxides in treatedwheat germ, which was stored at 50° C. with various antioxidants.

FIG. 11 α-tocopherol concentration in treated wheat germ, which wasstored at 50° C. with various antioxidants.

FIG. 12 Peroxide values of untreated wheat germ, which was stored at 50°C. with various antioxidants.

FIG. 13 Concentration of conjugated diene-hydroperoxides in untreatedwheat germ, which was stored at 50° C. with various antioxidants.

FIG. 14 α-tocopherol concentration in untreated wheat germ, which wasstored at 50° C. with various antioxidants.

FIG. 15 Peroxide value of corn oil, which was treated with respectively10% of various solvent agent extracts and stored at 60° C.

FIG. 16 Concentration of conjugated diene-hydroperoxides in corn oil,which was treated with respectively 10% of various solvent agentextracts and stored at 60° C.

FIG. 17 α-Tocopherol-concentration in corn oil, which was treated withrespectively 10% of various solvent agent extracts and stored at 60° C.

FIG. 18 Peroxide value of corn oil, which was treated with respectively20% of various solvent agent extracts and stored at 60° C.

FIG. 19 Concentration of conjugated diene-hydroperoxides in corn oil,which was treated with respectively 20% of various solvent agentextracts and stored at 60° C.

FIG. 20 α-Tocopherol-concentration in corn oil, which was treated withrespectively 20% of various solvent agent extracts and stored at 60° C.

FIG. 21 Peroxide value of wheat germ, which was stored at 50° C. withvarious concentrations of roasted wheat germ.

FIG. 22 Concentration of conjugated diene-hydroperoxide in wheat germ,which was stored at 50° C. with various concentrations of roasted wheatgerm.

FIG. 23 α-Tocopherol-concentration in wheat germ, which was stored at50° C. with various concentrations of roasted wheat germ.

FIG. 24 Peroxide value of wheat germ, which was stored at 40° C. withvarious concentrations of roasted wheat germ.

FIG. 25 Concentration of conjugated diene-hydroperoxide in wheat germ,which was stored at 40° C. with various concentrations of roasted wheatgerm.

FIG. 26 α-Tocopherol-concentration in wheat germ, which was stored at40° C. with various concentrations of roasted wheat germ.

FIG. 27 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, fresh wheat germ and stored at 60° C.

FIG. 28 Concentration of conjugated diene-hydroperoxides in tocopherolcontaining corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, fresh wheat germ and stored at 60° C.

FIG. 29 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, defatted wheat germ and stored at 60° C.

FIG. 30 Concentration of conjugated diene-hydroperoxides in tocopherolcontaining corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, defatted wheat germ and stored at 60° C.

FIG. 31 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousethanolic extracts of wheat germ, which were roasted at varyingtemperatures.

FIG. 32 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with ethanolicextracts obtained in varying manners.

FIG. 33 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousamounts of an ethanolic Soxhlet-extract.

FIG. 34 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousantioxidants.

DETAILED DESCRIPTION OF THE INVENTION

In the following the invention will be described in greater detail onthe basis of the illustrative embodiments with reference to the figures.

EXAMPLE 1

Definition/Roasting of Wheat Germ

The subject of the following research or, as the case may be, treatment,was three different samples of wheat germ:

a) Fresh wheat germ from a local market.

b) Roasted wheat germ: fresh wheat germ were filled in a 5-ml flask withglass stoppers and maintained for 20 minutes in a metal-block (typeS-35-240, from the company Liebisch, Germany) at a temperature of 160°C. Subsequently the thus roasted wheat germ was shock cooled with liquidnitrogen and utilized in the following research.

c) Roasted defatted wheat germ: Fresh wheat germ was defatted, extractedby subjecting for 14-16 hours to a Soxhlet-extraction with n-hexane.Subsequently the thus defatted wheat germ was roasted and furthertreated as under b).

EXAMPLE 2

Extraction of Roasted Wheat Germ with Various Extraction Solutions

Fresh wheat germ was roasted according to Example 1 b). Respectively 40g of the obtained roasted wheat germ was cooled, extracted multipletimes with a total of 100-300 ml of the extraction solution (a)diethylether, (b) acetone or, as the case may be, (c) ethanol, so that atotal of three extracts resulted. Each of these three extracts wasconcentrated in vacuum at 35° C. using a rotation evaporator, so thatthe remaining extract volume was 20 ml. Thus 1 ml of extract containedthe contents of 2 g roasted wheat germ. Each of the concentratedextracts was quantitatively transferred to a 20 ml-flask and stored inthe dark at −30° C. until further use.

Remarks

In the following examples the dosing of antioxidants in the treatment offoodstuffs is given in percentages. Insofar as the dosing data concernsthe extract of roasted wheat germ, they are to be understood as follows:

A dosing of for example 10% means that the extract of 10 g wheat germ isadded to 100 g foodstuffs (for example wheat germ, corn oil, wheat oil).This corresponds in accordance with the above procedure to an additionof 5 ml concentrated extract.

EXAMPLE 3

Comparison Testing for Stabilization of Wheat Germ Oil with VariousAntioxidants

3.1. First a total of 4 samples of respectively 50 g wheat germ oil weresubjected to stabilization tests.

For this the samples were filled into open beakers with a diameter ofrespectively 8.6 cm. Then three of the samples were subjected to variousantioxidants with stirring for 10 minutes, and namely with

Ascorbylpalmitate (0.02 weight %) as example for an antioxidativeeffective metal-chelate complex-former,

BHA (0.02 weight %) as an example of a phenolic antioxidant or, as thecase may be,

An inventive ethanol extract according to Example 2c (20%, see remarksfor Example 2).

The fourth sample was not supplemented with an antioxidant and served ascontrol.

The samples were stored at 50° C.

3.2. The stabilization test was repeated with otherwise identicalconditions, however the storage temperature was 60° C.

The oxidative stability of the various samples (according to 3.1 and3.2) was determined by repeated analysis, wherein at 24-hour intervalsrespectively the peroxide value, the concentration of conjugateddiene-hydroperoxides and the concentration of α-tocopherol wasdetermined. The peroxide value and the hydroperoxide-concentrationthereby served as empirical value for lipid-oxidation.

The results of the measurements are set forth in FIGS. 1-6:

There is shown:

FIG. 1 Peroxide values of conventional wheat germ oil, which was storedat 50° C. with various antioxidants.

FIG. 2 Concentration of conjugated diene-hydroperoxides in conventionalwheat germ oil, which was stored at 50° C. with various antioxidants.

FIG. 3 Concentration of α-tocopherol in conventional wheat germ oil,which was stored at 50° C. with various antioxidants.

FIG. 4 Peroxide values of conventional wheat germ oil, which was storedat 60° C. with various antioxidants.

FIG. 5 Concentration of conjugated diene-hydroperoxides in conventionalwheat germ oil, which was stored at 60° C. with various antioxidants.

FIG. 6 Concentration of α-tocopherol in conventional wheat germ oil,which was stored at 60° C. with various antioxidants.

(Control=Control Sample; BHA=Butyl-hydroxyanisole; Alc.anti-extr.=inventive ethanolic extract according to Example 2c;A/p=Ascorbyl-palmitate)

As can be seen from the comparison of FIGS. 1-3 with FIG. 4-6, theoxidation rate at 60° C. was, as expected, higher than at 50° C., andthe induction time at 60° C. was shorter.

The determination of the peroxide-value showed that the 20% ethanolicextract of roasted wheat germ possessed an antioxidative defect whichwas better than that of BHA, however slightly lower than that ofascorbylpalmitate (see FIG. 1 and 4, in which the increase in theperoxide value correlated to an increase in autooxidation products inwheat germ oil).

The measurements for concentration of conjugated diene-hydroperoxide inwheat germ oil corresponded to the results from the determination of theperoxide-value (see FIG. 2 and 5, in which the increase in thehydroperoxide concentration represented an increase of autooxidationproducts in wheat germ oil).

The changes in α-tocopherol concentration in wheat germ oil shown inFIG. 3 and 6, which served as an indicator for the stability thereof,likewise confirmed the results of the examination of peroxide-value andfor concentration of conjugated diene-hydroperoxide. A reduction in theα-tocopherol concentration is herein to be considered as an analog of anincrease in the peroxide value and the concentration of conjugateddiene-hydroperoxides.

Rancimat®-measurements confirmed again the results of the series ofmeasurements collected in the figures.

EXAMPLE 4

Comparative Test for Stabilization of Tocopherol-free Corn Oil withVarious Antioxidants

Four samples of respectively 50 g tocopherol-free corn oil (“strippedcorn oil”) were tested. These samples were filled into open beakers witha diameter of respectively 8.6 cm. Then three of the samples weresupplemented with various antioxidants with stirring for 10 minutes, andnamely with ascorbylpalmitate (0.02 weight %), BHA (0.02 weight %) or,as the case may be, an ethanolic extract according to Example 2c (20%).The fourth sample was not supplemented with an antioxidant and servedfor control purposes.

The samples were stored at 60° C. The oxidative stability of the varioussamples was determined with repeated analysis wherein at 24-hourintervals respectively the peroxide value and the concentration ofconjugated diene-hydroperoxides was determined, see FIGS. 7 and 8.

There is shown:

FIG. 7 Peroxide value in tocopherol-free corn oil, which was stored at60° C. with various antioxidants.

FIG. 8 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 60° C. with variousantioxidants.

(Control=Control Sample: BHA=Butyl-hydroxyanisole; Alc.anti-extr.=inventive ethanolic extract according to Example 2c;A/p=Ascorbyl-palmitate)

Both measurement methods lead to the result, that the antioxidativeeffect of the 20% ethanolic extract of roasted wheat germ was greaterthan that of BHA and ascorbylpalmitate. If one considers the resultsshown in FIG. 8 of hydroperoxide-formation, then it would appear thatascorbylpalmitate (A/p) at a certain concentration level even has apro-oxidative effect.

EXAMPLE 5

Comparative Test for Stabilization of Wheat Germ with VariousAntioxidants

Wheat germ from local markets are as a rule pre-stabilized (treated), inthat they are warmed with hot air or hot steam, in order to inactivatethe naturally contained enzymes, which otherwise contribute to thespoiling of the wheat germ. Four batches of respectively 500 g of the sopre-stabilized (treated) fresh wheat germ as well as—parallelthereto—four corresponding samples of fresh, untreated wheat germaccording to Example 1a) were sprayed with (a) 20 ml ethanol (forcontrol purposes), (b) 20 ml of a 0.01% BHA-solution in ethanol, (c) 20ml of a 0.01% ascorbylpalmitate-solution in ethanol or, as the case maybe, (d) 20 ml of a 8% solution of the ethanolic extract of roasted wheatgerm according to Example 2. Each of the eight total batches was spreadout into bowls, and namely such that the height of the wheat germ layerin no bowl was higher than 1 cm. The batches were stored at 50° C.

Using a conventional Soxhlet apparatus and with pentane/dichloromethane(2:1) as extraction agent, wheat germ oil samples were extracted inweekly intervals from the batches. The germ oil extracts were filtered,dried for 24 hours over dehydrated sodium sulfate, and then filteredagain. The extraction agents were removed under high vacuum at 35° C.The resulting raw oil was directly examined.

The oxidative stability of the wheat germ was analyzed, in that for theobtained oil-samples the peroxide value, the concentration of conjugateddiene-hydroperoxide and the concentration of α-tocopherol wasdetermined.

The results represented in FIGS. 9 through 14 show that the ethanolicextract of roasted wheat germ was better suited for stabilization bothof treated as well as untreated wheat germ than the conventionalantioxidants BHA and ascorbylpalmitate.

There is shown:

FIG. 9 Peroxide values of treated wheat germ, which was stored at 50° C.with various antioxidants.

FIG. 10 Concentration of conjugated diene-hydroperoxides in treatedwheat germ, which was stored at 50° C. with various antioxidants.

FIG. 11 α-tocopherol concentration in treated wheat germ, which wasstored at 50° C. with various antioxidants.

FIG. 12 Peroxide values of untreated wheat germ, which was stored at 50°C. with various antioxidants.

FIG. 13 Concentration of conjugated diene-hydroperoxides in untreatedwheat germ, which was stored at 50° C. with various antioxidants.

FIG. 14 α-tocopherol concentration in untreated wheat germ, which wasstored at 50° C. with various antioxidants.

(Control=Control Sample: BHA=Butyl-hydroxyanisole; Alc.anti-extr.=inventive ethanolic extract according to Example 2c;A/p=Ascorbyl-palmitate)

EXAMPLE 6

Comparison Test for Stabilization of Corn Oil with Various Extracts ofRoasted Wheat Germ

Here it is tested whether a difference in oxidative effect of thecorresponding extract of roasted wheat germ is achieved withextraction-solution agents of varying polarity. For this the stabilizingeffect of extracts of three foodstuff-acceptable extraction-solutionagents of various polarity were tested on corn oil (as example of aplant oil), in this at concentration levels of 10% and 20%:

A total of 6 corn oil samples were treated with 10 or as the case may be20% of a diethylether-acetone or as the case may be ethanol extract ofroasted wheat germ; the production of this extract is described inExample 2. The oxidative stability of the samples stored at 60° C. wasdetermined by repeated analysis, wherein at 24-hour intervalsrespectively the peroxide value, the concentration of conjugateddiene-hydroperoxides and the concentration of α-tocopherol wasdetermined.

At concentration levels of 10% the antioxidative effects of the etherand acetone extracts were similar, however, respectively lower than theantioxidative effect of the ethanolic extract, as can been seen from thefollowing FIGS. 15-17, in which the results of peroxide value,concentration of conjugated diene-hydroperoxides and concentration oftocopherol are indicated.

The clear antioxidative effect of the ethanolic extract of roasted wheatgerm is even more distinct at the concentration level of 20%. This canbe seen from FIGS. 18-20.

There is shown:

FIG. 15 Peroxide value of corn oil, which was treated with respectively10% of various solvent agent extracts and stored at 60° C.

FIG. 16 Concentration of conjugated diene-hydroperoxides in corn oil,which was treated with respectively 10% of various solvent agentextracts and stored at 60° C.

FIG. 17 α-Tocopherol-concentration in corn oil, which was treated withrespectively 10% of various solvent agent extracts and stored at 60° C.

FIG. 18 Peroxide value of corn oil, which was treated with respectively20% of various solvent agent extracts and stored at 60° C.

FIG. 19 Concentration of conjugated diene-hydroperoxides in corn oil,which was treated with respectively 20% of various solvent agentextracts and stored at 60° C.

FIG. 20 α-Tocopherol-concentration in corn oil, which was treated withrespectively 20% of various solvent agent extracts and stored at 60° C.

(Control=Control Sample)

EXAMPLE 7

Test for Stabilization of Untreated Wheat Germ by Mixing with RoastedWheat Germ

Four batches of 500 g of fresh untreated wheat germ were mixed with 0weight %, 4 weight %, 8 weight %, or, as the case may be, 16 weight %roasted wheat germ.

A further 500 g sample of fresh wheat germ was divided into ten 50 gsamples, which were then transferred respectively to a petri dish of 19cm diameter and were subjected to microwave treatment at 600 watt for 5minutes. The ten 50 g samples were then again recombined.

Each of the thus 5 total samples of 500 g was spread out in 2 bowls andstored at 50° C.

The oxidative stability of the samples was determined by repeatedanalysis, wherein at 24-hour intervals respectively the peroxide value,the concentration of conjugated diene-hydroperoxides and theconcentration of α-tocopherol was determined, see FIGS. 21-23.

The stabilization of wheat germ by addition of small amounts of roastedwheat germ was more effective than a microwave treatment, which isconventionally employed to stabilize the lipolytic enzyme of the germ.The addition of 4% roasted wheat germ had better antioxidative effect at50° C. than the addition of 8% or 16% roasted wheat germ. At addition of16% roasted wheat germ, a prooxidative effect was discovered as a matterof fact in the first 30 days.

The test was repeated with a further group of samples, whereinrespectively 500 g fresh untreated wheat germ was mixed with 8 weight %,2 weight %, 4 weight %, 6 weight % or, as the case may be, 8 weight %roasted wheat germ. With otherwise identical tests and evaluationconditions, the samples were stored however at 40° C.

As can be seen from FIGS. 24-26, the addition of 2%, 4% and 6% roastedwheat germ had an approximately equal stabilizing effect on the freshwheat germ at a storage temperature of 40° C. At addition of 8% roastedwheat germ the antioxidative effect was however no longer so distinct aswith the lower concentrations.

There is shown:

FIG. 21 Peroxide value of wheat germ, which was stored at 50° C. withvarious concentrations of roasted wheat germ.

FIG. 22 Concentration of conjugated diene-hydroperoxide in wheat germ,which was stored at 50° C. with various concentrations of roasted wheatgerm.

FIG. 23 α-Tocopherol-concentration in wheat germ, which was stored at50° C. with various concentrations of roasted wheat germ.

FIG. 24 Peroxide value of wheat germ, which was stored at 40° C. withvarious concentrations of roasted wheat germ.

FIG. 25 Concentration of conjugated diene-hydroperoxide in wheat germ,which was stored at 40° C. with various concentrations of roasted wheatgerm.

FIG. 26 α-Tocopherol-concentration in wheat germ, which was stored at40° C. with various concentrations of roasted wheat germ.

(RWG=roasted wheat germ; microwave-WG=microwave treated wheat germ)

EXAMPLE 8

Preparative HPLC-Fractionation of the Ethanolic Extract of Roasted,Fresh or, as the Case may be, Defatted Wheat Germ

Two ethanolic extracts of roasted wheat germ were produced.

The first ethanolic extract originated from roasted fresh wheat germaccording to Example 1 b; the second ethanolic extract originated fromroasted, defatted wheat germ according to Example 1 c.

These two extracts were fractionated using preparative HPLC under use ofa diol-column (Lichrosorb, 250×25 ml, particle size 7 μm, Merck,Darmstadt, Germany). The elution system was respectively dichloromethane(I) and methanol (II). The gradient was respectively 100% I for 10minutes and was then brought up to 50% II by linear increase of theproportion II up to the 100^(th) minute; after further 10 minutes it wasrespectively increased to 100% II. At these gradients the system wasmaintained up to the 130^(th) minute. The flow-through rate was 10 mlmin⁻¹, and the injection volume was 2 l.

The respective eluate was collected in a fraction collector. A total ofsix fractions were obtained, and namely one fraction for the timeinterval from 0-32 minutes (1), 32-44 minutes (2), 44-56 minutes (3),56-76 minutes (4), 76-86 minutes (5) and 86-130 minutes (6). Thefractions were concentrated in a vacuum at 40° C. and quantitativelytransferred to a 5 ml measuring flask. It was respectively filled asmuch as possible with ethanol. The fractions were stored at −30° C.until they were used in the comparative testing in Example 9.

EXAMPLE 9

Comparison of Antioxidative Effect of the Fractions from theFractionation According to Example 8

Four ethanolic fractions according to Example 8 were tested for theirstabilizing properties. Corn oil was employed as the foodstuff to bestabilized, and namely on the one hand tocopherol-free corn oil and onthe other hand corn oil with a natural component of tocopherol.

1. First, samples of respectively 10 g tocopherol-free corn oil(“stripped corn oil”) were employed. To these samples was addedrespectively 2.5 ml from one of the 6 fractions of the ethanolic extractof roasted fresh wheat germ or, as the case may be, roasted defattedwheat germ. For control purposes a 1 ml sample of the original ethanolicextract of roasted wheat germ (either fresh, that is, fat containing, ordefatted) was treated with 1.5 ml ethanol, and a further control samplecontained 2.5 ml ethanol. The samples were respectively stirred for 10minutes.

Subsequently the samples were stored at 60° C.

The oxidative stability was determined by repeated analysis, wherein at24 hour intervals respectively the concentration of conjugateddiene-hydroperoxide was determined.

2. The comparison test was repeated with tocopherol-containing corn oil,in order also to test insofar the stability of the fractions.

The results of the tests are collectively represented in FIGS. 27-30.

There is shown:

FIG. 27 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, fresh wheat germ and stored at 60° C.

FIG. 28 Concentration of conjugated diene-hydroperoxides in tocopherolcontaining corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, fresh wheat germ and stored at 60° C.

FIG. 29 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, defatted wheat germ and stored at 60° C.

FIG. 30 Concentration of conjugated diene-hydroperoxides in tocopherolcontaining corn oil, which was treated with fractions 1-6 from theethanolic extract of roasted, defatted wheat germ and stored at 60° C.

(Fr.=fractions; Alc. anti-extr=ethanolic extract of fresh wheat germ;Def alc anti-extr=ethanolic extract of defatted wheat germ)

The experiments showed first that the antioxidative effect of therespective total extract of fresh or defatted wheat germ was better thanthe effect of the individual fractions, see FIGS. 27-30.

In the comparison of the extracts of fresh and defatted wheat germ,surprisingly the extract of fresh (that is fat containing) wheat germproved itself to be more effective; this can be seen by the side by sidecomparison of the FIGS. 27 and 29 as well as the side by side comparisonof FIGS. 28 and 30.

These results are possibly based upon a synergistic effect between thevarious constituent compounds of the raw extract of fresh wheat germ.

It was further determined, that the differences in the antioxidativeeffect between the respective 6 fractions (fresh or fat-free) duringtesting with use of tocopherol-free corn oil was very small, see FIGS.27 and 29.

In the test using corn oil which contained tocopherol, fractions 5 (bothfat containing as well as defatted) and 6 (defatted) showed the highestantioxidative effectiveness within the tested fractions, see FIGS. 28and 30. The differences between the fractions were (in comparison withthe of tocopherol-free corn oil) generally higher, see FIGS. 27-30.

EXAMPLE 10

Comparison Test for Experimentation of the Influence of the RoastingTemperature upon the Antioxidative Effect of Extracted Wheat GermExtract in the Treatment of Tocopherol-free Corn Oil

Analogously to the production of roasted wheat germ according to Example1 b) fresh wheat germ was filled into a 5-ml flask with glass stopperand maintained for 20 minutes in a metallblock (Type S-35-240, producedby the company Liebisch, Germany) at a temperature at

a) 140° C.

b) 160° C.

c) 180° C. and

d) 200° C.

Subsequently the wheat germ roasted at different temperatures were shockcooled with liquid nitrogen.

Respectively 40 g of the wheat germ produced by the different roastingtemperatures according to a)-d) were (analogous to Example 2 c))extracted multiple times with ethanol, so that a total of four extractsresulted. Each of these four extracts was concentrated using a rotationevaporator at 35° C. in vacuum, so that the remaining extract volume was20 ml. Each 1 ml extract thus contained the content substances of 2 groasted wheat germ. Each of the four concentrated extracts wasquantitatively transferred to a 20 ml flask and stored at −30° C. in thedark until further use.

Analogously to Example 4, 5 samples of respectively 50 g tocopherol-freecorn oil (“stripped corn oil” ) were examined. These samples were filledinto an open beaker with a diameter of respectively 8.6 cm. To four ofthe samples there was then added with stirring for 10 minutesrespectively one of the four ethanolic extracts of the wheat germroasted at different temperatures (dosage 20%, see remarks in Example2). No antioxidative ethanolic extract was added to the fifth sample andthis served for control purposes.

The five samples were stored in a dry chamber at 50° C. The oxidativestability of the various samples was determined by repeated analysis,wherein respectively at intervals of multiple days (beginning after oneday) the concentration of conjugated diene-hydroperoxides wasdetermined, see FIG. 31.

There is shown:

FIG. 31 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousethanolic extracts of wheat germ, which were roasted at varyingtemperatures.

(Control=Control sample: the indicated temperatures associated with themeasurement points in FIG. 31 indicate the roasting temperature of theassociated samples)

FIG. 31 shows that the antioxidative effect of the ethanolic extractincreases with increasing roasting temperature of the underlying wheatgerm. At roasting temperatures above approximately 160° C. theimprovements, in comparison with the extract of wheat germ which wasroasted at lower temperatures, begin however to be less pronounced. Anincrease in the roasting temperature above the temperature of 160° C.thus brings about only small improvements with respect to theantioxidative characteristics of the corresponding extract. At roastingtemperatures from above 160-170° C. there occurs instead a strongerformation of suspected toxicological pyrolysis products (IQ-compounds,that is, mutagenic hetercyclic aromatic amines); for this reason higherroasting temperatures are not particularly desired.

EXAMPLE 11

Testing for Researching the Influence of the Extraction Process on theAntioxidative Effect of a Corresponding Ethanolic Extract

Two ethanolic extracts prepared in different manner from roasted wheatgerm according to Example 1 b) were compared, namely:

(a) an extract according to Example 2 c) and

(b) an ethanolic Soxhlet-extract, which after 20 hours of continuousSoxhlet-extraction of 40 g roasted wheat germ according to Example 1 b)with ethanol at approximately 2 passes per hour was obtained by asubsequent concentration according to Example 2.

Analogous to Example 4, there were then tested 3 samples of respectively50 g tocopherol-free corn oil (“stripped corn oil”). These samples werefilled into an open beaker with a diameter of respectively 8.6 cm.Ethanolic extracts produced in respectively one of the two differentways was added with stirring for 10 minutes to the two samples (dosage20%, see remarks in Example 2). Ethanolic extract was not added to thethird sample and this served for control purposes.

The samples were stored at 50° C. in a dry chamber. The oxidativestability of the various samples was determined by repeated analysiswherein in intervals of multiple days respectively the concentration ofconjugated diene-hydroperoxides was determined, see FIG. 32.

There is shown:

FIG. 32 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with ethanolicextracts obtained in varying manners.

(Control=control samples; EtOH=ethanolic extract according to Example2c; Soxhlet-EtOH=ethanolic Soxhlet-extract according to Example 11b)

From FIG. 32 it can be seen that a continuous extraction of roastedwheat germ (plot Soxhlet-EtOH) in comparison with an extractionaccording to Example 2 c) (plot EtOH) does not result in a clearincrease in the antioxidative effect of the resulting extract.

EXAMPLE 12

Test for Determining the Influence of the Extract Amount on theOxidative Effect of an Ethanolic Soxhlet-Extract

An ethanolic Soxhlet-extract was employed, which was produced accordingto Example 11 b).

Analogously to Example 4, five samples of respectively 50 gtocopherol-free corn oil (“stripped corn oil”) were tested. Thesesamples were filled into an open beaker with a diameter of respectively8.6 cm. To four of the samples there was then added, with stirring for10 minutes, different amounts of a Soxhlet-extract, and namely

(a) 5% Soxhlet-extract

(b) 10% Soxhlet-extract

(c) 20 Soxhlet-extract

(d) 40% Soxhlet-extract,

respectively according to the remarks in Example 2.

Ethanolic Soxhlet-extract was not added to the fifth sample and thisserved for control purposes.

The samples were stored at 50° C. in a dry chamber. The oxidativestability of the various samples was determined by repeated analysis,wherein at intervals of several days respectively the concentration ofconjugated diene-hydroperoxides was determined, see FIG. 33.

There is shown:

FIG. 33 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousamounts of an ethanolic Soxhlet-extract.

(Control=control sample; the percentages associates with the measuringpoints in Example 31 [sic] indicate the different employed amounts ofextract)

From FIG. 33 it can be seen that the variation of the extract amounts of5% to 10% brings about a significant improvement in the antioxidativeeffect.

In the transition from 10% to 20% the improvement in antioxidativeeffect is however only small.

In the transition from 20% to 40% no significant improvement in theantioxidative effect can any longer be determined.

EXAMPLE 13

Comparative Test for Stabilization of Tocopherol-free Corn Oil withEthanolic Extracts of Different Roasted Grain Types

There was tested

a) an ethanolic extract according to Example 2 c), that is, an extractbased upon the roasted wheat germ according to Example 1 b), as well as

b) an ethanolic extract of roasted corn germ, which was produced fromroasted corn germ analogous to Example 2 c), which were roastedanalogously to Example 1 b),

c) an ethanolic extract roasted barley germ, which was producedanalogously to Example 2 c) from roasted barley germ, which was roastedanalogously to Example 1 b), and

as further comparative substance there was used

d) ascorbylpalmitate.

Four samples of respectively 50 g tocopherol-free corn oil (“strippedcorn oil”) were examined. These samples were filled into open beakerswith a diameter of respectively 8.6 cm. To the three examples there wereadded the antioxidants described under paragraphs a)-c) with stirringfor 10 minutes, that is with wheat germ extract, corn germ extract andbarley germ extract (dosing respectively 20%, see the remarks forExample 2) or as the case may be ascorbylpalmitate (dosing 0.02 weight%). No antioxidant was added to the fifth sample and this served forcontrol purposes.

The samples were stored at 50° C. The oxidative stability of the varioussamples was determined by repeated analysis, wherein at intervals ofseveral days (beginning after the first day) respectively theconcentration of conjugated diene-hydroperoxides was determined, seeFIG. 34.

There is shown:

FIG. 34 Concentration of conjugated diene-hydroperoxides intocopherol-free corn oil, which was stored at 50° C. with variousantioxidants.

(Control=control sample; a=wheat germ extract; b=corn germ extract;c=barley germ extract; d=ascorbylpalmitate)

From FIG. 34 can be seen that not only the wheat germ extract, butrather also the corn germ extract and the barley germ extract have asignificant antioxidative effect.

Ascorbylpalmitate demonstrated an antioxidative effect at the storagetemperature of 50° C., which for the first 10 days was somewhat weakerthan the wheat germ extract, however strong than the barley or corn germextract. The rapid advance in the autooxidation from the 10^(th) to the14^(th) day and the extrapolation of the curve for ascorbylpalmitatebeyond the 14^(th) day however allows one to expect a pro-oxidativeaction at a later point in time. This is in agreement with the observedpro-oxidative effect of the ascorbylpalmitate in Example 4.

The tested extracts of wheat, barley and corn germ do not lead toexpectation of pro-oxidative effect, even after longer storage times.

What is claimed is:
 1. Foodstuff or cosmetic agent, including astabilizing effective amount of an extract obtained by a processcomprising: extracting non-enzymatically browned grain germ separatedfrom other components of whole grain with a solvent or solvent mixturehaving a E_(T) ^(N)-value of between 0.6 and 0.8, followed by optionallyseparating the extraction agent.
 2. An antioxidatively effective extractfor stabilization of foodstuffs, wherein the extract is produced by aprocess comprising: extracting non-enzymatically browned grain germseparated from other components of whole grain with a solvent or solventmixture having a E_(T) ^(N)-value of between 0.6 and 0.8 as extractionagent, collecting said extract and extraction agent, followed byoptionally separating the extraction agent.
 3. Process for production ofan antioxidatively effective extract, comprising: extractingnon-enzymatically browned grain germ, separated prior to non-enzymaticbrowning from other components of whole grain, with a solvent or solventmixture having a E_(T) ^(N)-value of between 0.6 and 0.8 as extractionagent, collecting said extract and extraction agent, followed byoptionally separating the extraction agent.
 4. Process according toclaim 3, wherein the extraction agent is selected from the groupconsisting of ethanol and ethanolic solutions.
 5. Process according toclaim 3, wherein the grain germ is selected from the group consisting ofwheat, barley and corn germ.
 6. Process according to claim 3, whereinsaid extract is subjected to fractionation, whereby aroma and/or colorimparting minor ingredients of the extract are separated therefrom. 7.Process for production of an antioxidatively effective extract,comprising: extracting roasted grain germ, separated prior to roastingfrom other components of whole grain, with a solvent or solvent mixturehaving a E_(T) ^(N)-value of between 0.6 and 0.8 as extraction agent,collecting said extract and extraction agent, followed by optionallyseparating the extraction agent.
 8. Process according to claim 7,wherein the grain germ is browned at a roasting temperature in the rangeof between 120° C. and 170° C.
 9. Process according to claim 8, whereinthe grain germ is browned at a roasting temperature in the range ofbetween 140° C. and 160° C.
 10. Process for stabilization of foodstuffsor cosmetic agents, comprising: extracting non-enzymatically brownedgrain germ separated from other components of whole grain with a solventor solvent mixture having a E_(T) ^(N)-value of between 0.6 and 0.88 asextraction agent, collecting said extract and extraction agent, followedby optionally separating the extraction agent, and treating thefoodstuff or cosmetic agent with a stabilizing effective amount of theextract or fraction of the extract.
 11. A process according to claim 10,wherein said foodstuff is a lipid rich foodstuff.